ER Diagram: The Local Council Is Planning To Implement A Dat
ER Diagramthe Local Council Is Planning To Implement A Databa
Task A – ER Diagram The local council is planning to implement a database system to help track players that sign up to play soccer. Data needs to be maintained for each team, the players their parents. Also, data needs to be stored for the coaches for each team. Consider the following set of requirements to maintain this database:
- A Team is made up of many Players, and also has a Coach, and each Player has a Parent.
- Each Team has an ID number, name, and colours.
- Each Player has an ID number, first name, last name, and age.
- Each Coach has an ID number, first name, last name, and home phone number.
- Each Parent has an ID number, last name, first name, Home phone number, and Home Address (Street, City, State, and Postal Code).
- A Player must have one and only one Team.
- A Team must have many Players.
- A Team may or may not have a Coach.
- A Coach must have one and only one Team.
- A Team may have many Coaches.
- A Player must have at least one Parent, possibly more.
- A Parent must have a Player.
Draw a corresponding ER diagram based on the above requirements. Use UPPERCASE for entities, and Capitalisation of first letter for attributes. Underline primary key attributes and identify foreign keys. Indicate participation and cardinalities clearly, and specify relationship verbs.
Paper For Above instruction
The ER diagram for the soccer sign-up database encapsulates multiple entities, relationships, and constraints designed to effectively manage the data associated with teams, players, coaches, and parents. The primary entities include TEAM, PLAYER, COACH, and PARENT, each with specific attributes and primary keys. TEAM has attributes such as TeamID, Name, and Colours, serving as the primary key. Each PLAYER has a PlayerID, FirstName, LastName, and Age; each COACH has a CoachID, FirstName, LastName, and HomePhone. The PARENT entity includes ParentID, LastName, FirstName, HomePhone, and Address comprising Street, City, State, and PostalCode.
The relationships among entities are defined as follows: A TEAM is composed of multiple PLAYERS (One-to-Many), with a mandatory participation of Player in a Team. Each PLAYER has a mandatory association with exactly one TEAM. Consequently, the cardinality is 1..1 between Player and Team, and 1..N from Team to Player. Each Player must have at least one PARENT, but may have multiple, establishing a Many-to-Many relationship, which can be handled through an associative entity or a join table, e.g., PlayerParent. A Parent is associated with at least one Player.
The COACH entity exhibits optional association with TEAM, indicating that a TEAM may or may not currently have a Coach. However, a COACH must be assigned to exactly one TEAM. Multiple COACHES can be associated with a single TEAM.
The relationships are annotated with verbs: 'has,' 'belongs to,' 'coaches,' and 'has players,' to clarify the semantic meaning. The diagram ensures referential integrity by underlining primary keys and stating foreign keys, for example, TeamID in PLAYER and PlayerID in PARENT relationships. The participation constraints show that Player and Parent participation are total, whereas Coach participation with Team is optional.
Normalization Considerations in Database Design
While not directly specified in the ER diagram, normalization principles guide the design to reduce redundancy and dependency. The entities and relationships modeled aim for at least 3NF: each entity contains atomic attributes, and dependencies are structured to prevent update anomalies. For instance, separating coach information into a dedicated entity avoids repetition and ensures consistency. Similarly, modeling parent-children relations as a separate entity facilitates handling multiple parents per player, adhering to 1NF, 2NF, and 3NF standards.
Conclusion
The ER diagram effectively captures the requirements through entities, attributes, and relationships, providing a blueprint for implementing a relational database that facilitates tracking teams, players, coaches, and parents in the soccer sign-up context. Proper normalization enhances data integrity and efficiency in the database system.